Foldable structure of large-sized umbrella

ABSTRACT

A foldable umbrella includes a center rod having an upper end to which a primary crown is attached. A primary runner is movable along the central rod toward/away from the primary crown for opening/closing the umbrella. Pairs of secondary crown and runner are equally spaced around the primary crown and runner. A first intermediate bar has opposite ends pivoted to the primary crown and each secondary runner. A second intermediate bar has opposite ends pivoted to the primary runner and each secondary crown. The first and second intermediate bars intersect and are pivoted to each other whereby a parallelogram linkage is formed, which drives the secondary runners simultaneously with the movement of the primary runner in opening/closing the umbrella. A first rib bar extends radially from each secondary crown and a stretcher bar is arranged between and having ends pivoted to each first rib bar and the associated secondary runner. A canopy is attached to the crowns and supported by the rib bars whereby when the umbrella is open, the canopy is expanded by the secondary crowns and the rib bars. If desired, second rib bars may be pivoted to each secondary crown and radially extend therefrom for further supporting the canopy. Corresponding stretcher bars are provided between the second rib bars and the associated runners.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention generally relates to a large-sized umbrella, and in particular to a foldable frame of the large-sized umbrella.

[0003] 2. The Related Art

[0004] Large-sized umbrellas are widely used in a variety of applications, such as beach umbrellas and garden umbrellas, for shading intense sunlight. Most of the large-sized umbrellas have the similar structure. A typical example of the large-sized umbrellas is shown in FIG. 7 of the attached drawings. The large-sized umbrella comprises a central rod 10 along which a runner 12 is movable. A crown 11 is mounted to a top end of the central rod 10. A base 16 is mounted to a lower end of the central rod 10. A number of ribs 13 are pivoted to the crown 11 and radially extend therefrom. A stretcher 14 has opposite ends respectively pivoted to each rib 13 and the runner 12. A canopy 15 is attached to the ribs 13. Moving the runner 12 toward the crown 11 forces the stretchers 14 to drive the ribs 13 and thus the canopy 15 upward and thus opening the umbrella and moving the runner 12 downward away from the crown 11, the canopy 15 is closed.

[0005] The central rod 10 supports the ribs 13 and the canopy 15 in an expanded condition. However, the presence of the central rod 10 limits the utilization of the area shielded by the canopy 15 because the central rod 10 is in general located at a center position of the area shielded by the canopy 15. To make more exploitation of the shielded area, the size of the canopy 15 may be increased. However, the increase of the size of the canopy 15 requires a corresponding increase of the length of the ribs 13, which is, however, subject to the limitation of the overall length of the central rod 10.

[0006] Thus, it desired to have a foldable structure of large-sized umbrellas that overcomes the above problems.

SUMMARY OF THE INVENTION

[0007] An object of the present invention is to provide a large-sized umbrella having a foldable frame for supporting a large canopy.

[0008] Another object of the present invention is to provide a foldable structure of large-sized umbrellas capable of carrying canopies of different shapes.

[0009] To achieve the above objects, in accordance with the present invention, there is provided an umbrella comprising a center rod having an upper end to which a primary crown is attached. A primary runner is movable along the central rod toward/away from the primary crown for opening/closing the umbrella. Pairs of secondary crown and runner are equally spaced around the primary crown and runner. A first intermediate bar has opposite ends pivoted to the primary crown and each secondary runner. A second intermediate bar has opposite ends pivoted to the primary runner and each secondary crown. The first and second intermediate bars intersect and are pivoted to each other whereby a parallelogram linkage is formed, which drives the secondary runners simultaneously with the movement of the primary runner in opening/closing the umbrella. A first rib bar extends radially from each secondary crown and a stretcher bar is arranged between and having ends pivoted to each first rib bar and the associated secondary runner. A canopy is attached to the crowns and supported by the rib bars whereby when the umbrella is open, the canopy is expanded by the secondary crowns and the rib bars. If desired, second rib bars may be pivoted to each secondary crown and radially extend therefrom for further supporting the canopy. Corresponding stretcher bars are provided between the second rib bars and the associated runners. The number and the arrangement of the pairs of the secondary crown and runners can be arbitrary and the shape of the canopy can be changed in accordance therewith.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention will be apparent to those skilled in the art by reading the following description of preferred embodiments thereof, with reference to the attached drawings, in which:

[0011]FIG. 1 is a side elevational view of a large-sized umbrella constructed in accordance with the present invention;

[0012]FIG. 2 is similar to FIG. 1 but showing details of a foldable frame of the large-sized umbrella of the present invention in an expanded condition;

[0013]FIG. 3 is similar to FIG. 2 but showing the umbrella in a partially collapsed condition;

[0014]FIG. 4 is side elevational view of a foldable frame of the large-sized umbrella of the present invention;

[0015]FIG. 5 is a plan view showing a first example of a canopy of the umbrella of the present invention;

[0016]FIG. 6 is a plan view showing a second example of the canopy of the umbrella of the present invention; and

[0017]FIG. 7 is a side elevational view of a conventional large-sized umbrella.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] With reference to the drawings and in particular to FIGS. 1 and 2, a large-sized umbrella constructed in accordance with the present invention, generally designated with reference numeral 20, comprises a central rod 21 having a lower end mounted to a stand or base 27 for supporting the central rod 21 and thus the umbrella 20 in a substantially upright manner and an upper end (not labeled) supporting a foldable frame carrying a canopy 25.

[0019] Also referring to FIG. 4, the foldable frame comprises a primary runner 22 movable along the central rod 21 and a primary crown 23 mounted to the upper end of the central rod 21. A pair of secondary runner, also designated with reference numeral 22 for simplicity, and secondary crown, also designated with reference numeral 23 for simplicity, is arranged on one side of and radially spaced from the central rod 21 (or the primary crown 23). The primary and secondary crowns 23 are substantially at the same altitude and the same applies to the primary and secondary runners 22. A first intermediate bar 24 extends between the primary crown 23 and the secondary runner 22 and similarly a second intermediate bar 24 extends between the secondary crown 23 and the primary runner 22. Both ends of each intermediate bar 24 are pivoted to the crown 23 and the runner 22. The intermediate bars 24 intersect and are pivoted to each other by means of such as a rivet 26.

[0020] It is noted to have a balanced structure, it is desired to have a symmetrical configuration for the umbrella 20. Namely, another pair of secondary crown 23 and runner 22 is located on the opposite side of the central rod 21 as shown in FIG. 2. If desired, a number of pairs of secondary crowns and runners are equally spaced around the central rod 21 (or the primary crown 23). Similarly, intermediate bars 24 are connected between the primary crown and runner and the secondary crown and runner. This forms a number of parallelogram linkages, allowing the secondary crowns 23 and secondary runners 22 to move simultaneously between an open condition as shown in FIG. 2 and a closed condition as shown in FIG. 3. It is noted that the movement of the secondary crowns 23 is in a substantially radial direction with respect to the primary crown 23, while that of the secondary runners 22, in addition to the synchronous movement in a direction parallel to the central rod 21 with the primary runner, is in the substantially radial direction also. The canopy 25 is attached to the secondary crowns 23 whereby the radial movement of the crowns 23 expands the canopy 25.

[0021] A first rib bar, also designated with reference numeral 24 for simplicity, is pivoted to and extends from each secondary crown 23 radially and outwards for supporting the canopy 25 that is shown in phantoms in FIGS. 2 and 3. A stretcher bar, also designated with reference numeral 24, is arranged between and having ends pivoted to each first rib bar and the associated secondary runner. The stretcher bars and the rib bars are such that they form parallelogram with the adjacent intermediate bars 24. In this respect, all the bars 24 are pivoted to each other and the crowns 23 and the runners 22 and form parallelogram linkages. The foldable frame of the umbrella 20 is thus comprised of a number of parallelogram linkages. If desired, addition rib bars can be pivoted to and extend radially from each crown 23 for further supporting the canopy 25.

[0022] When the primary runner 22 is moved toward the primary crown 23, the parallelogram formed by the intermediate bars drives the secondary runners 22 and the secondary crowns 23 to simultaneously move with the primary runner 22 and the primary crown 23. The rib bars 24 and the stretcher bars 24 are also caused to move simultaneously thereby opening the umbrella 20 and expanding the canopy 25. When the primary runner 22 is moved away from the primary crown 23, the secondary runners 22 and the secondary crowns 23 are moved simultaneously due to the parallelogram linkages. Thus, the umbrella 20 is closed and the canopy 24 is collapsed.

[0023] In this way, the size of the canopy 25 can be effectively increased as compared to the conventional large-sized umbrellas without increase the length of the rib bars or intermediate bars.

[0024]FIG. 5 shows a top plan view of the umbrella 20 of the present invention wherein two pairs of secondary runners and crowns 23 are arranged on opposite side of the central rod 21 (namely the primary runner and the primary crown 23). The canopy 25 is rectangular and is supported by the rib bars 24 in the open condition.

[0025]FIG. 6 shows a top plan view illustrating a different arrangement of the secondary runners and crowns wherein four pairs of secondary runners and crowns are equally-spaced around the central rod 21 (and thus the primary crown 23) to support a square canopy 25. It is apparent other arrangements of the secondary crowns and runners are possible for supporting canopy of different shape.

[0026] In addition, the primary runner can be moved manually or by a power device. For example, a rope-pulley system driven by a manual crank arm can be employed to move the primary runner toward/away from the primary crown for opening/closing the umbrella. Other transmission system, such as rack-gear based system and other gear train based system, can also be employed.

[0027] Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims. 

What is claimed is:
 1. An umbrella comprising: a central rod having an upper end; a primary crown mounted to the upper end of the central rod and a primary runner movable along the central rod toward/away from the primary crown for opening/closing the umbrella; at least one pair of secondary runner and secondary crown respectively corresponding in position to the primary runner and crown and radially spaced therefrom; a first intermediate bar having opposite ends respectively pivoted to the primary crown and the secondary runner and a second intermediate bar having opposite ends respectively pivoted to the secondary crown and the primary runner; at least one first rib bar pivoted to each secondary crown and radially extending therefrom; a stretcher bar having ends respectively pivoted to each rib bar and the associated secondary runner; and a canopy attached to the crowns and supported by the rib bar.
 2. The umbrella as claimed in claim 1 comprising two pairs of secondary crowns and runners arranged on opposite sides of the primary crown and runner, second rib bars pivoted to the primary and secondary crowns and radially extending therefrom for supporting a rectangular canopy.
 3. The umbrella as claimed in claim 1 comprising four pairs of secondary crowns and runners equally spaced around the primary crown and runner for supporting a square canopy.
 4. The umbrella as claimed in claim 1, wherein the first and second intermediate bars intersect and are pivoted to each other.
 5. The umbrella as claimed in claim 4, wherein the bars form at least one parallelogram linkage. 